HistFactory

[cranmer]

It would be nice to start with a reference to the existing documentation:

http://inspirehep.net/record/1236448

mention HistFitter as an extension of HIstFactory

Then 4 sub-pages:

• the HistFactory schema. eg. the mapping of the different OverAllSys etc. to specific math (initially pointing the documentation above, later copying the specific mathematical equations).

• migrate the the XML documentation https://twiki.cern.ch/twiki/bin/view/RooStats/HistFactoryXMLReference

• C++ documentation / example

• python documentation / example http://ghl.web.cern.ch/ghl/html/HistFactoryDoc.html